The Donald’s loss was more significant than Ted Cruz’s win as the GOP’s political world finally starts to make sense.

So, it turns out that you can’t call Iowa voters “stupid,” skip a debate in Des Moines because you don’t like the moderators and still expect to prevail in the state’s caucuses. Who knew?

Donald Trump’s loss Monday night, which is far more consequential than Ted Cruz’s victory, could mean a return to Republican normalcy in an election year that has been almost freakish. Mr. Trump’s poll numbers have soared above his rivals’...